Adjusting-post.



B. AMES.

ADJUSTING POST.

APPLICATON FILED MAY 21. 1913.

1,140,433. Patented May 25,1915.

V: inn-nil WITNESSES.- IIVVENTOR.

MA M/QM M 012% %W%7Zq ATTORNEY.

THE NORRIS PETERS CO. FHOTO-LITHO., WASHINGmN. D c

BUTLER AMES, 0F LOWELL, MASSACHUSETTS.

ADJUSTING-POST.

Specification of Letters Patent.

Patented May 25, 1915.

Application filed May 21, 1913. Serial No. 769,045.

To all whom it may concern:

Be it known that I, BUTLER AMEs, a citizen of the United States,residing at Lowell, in the county of Middlesex and State ofMassachusetts, have invented certain new and useful Improvements inAdjusting-Posts, of which the following is a specification.

This invention relates to adjusting posts for adjusting the tension ofarmature springs or spring armatures used in connection with inductioncoils and especially with such as are known as spark coils.

My device may be used in connection with many forms of armature springsbut I prefer to use it in connection with the spring armature shown inthe drawings herewith upon which I have applied for Letters Patent ofeven date herewith, filed May 21, 1913, Serial Number 7 69,043 entitledArma ture springs. Y

The purpose of my adjusting device is to permit the tension on thespring armature or armature spring to be adjusted at the minimum pointand to then lock the parts in place in such a manner that within alimited range, greater tension may be applied but the tension cannot bereduced below the minimum point or increased above an allowablepredetermined maximum.

Figure 1 is a plan view from the top of my device on a coil. Fig. 2 is aplan view from the bottom of the top non-conducting plate. Fig. 3 is anenlarged sectional side elevation. Fig. 4 is an end elevation from thebottom of Fig. 1. Fig. 5 is a plan view of the spring armature.

A suitable case M incloses the usual core N, primary and secondarywindings, condenser and proper electrical connections. Upon the top ofthe case M and insulated therefrom by a non-conducting plate B, is thetop metal plate A to which the members of my device are attached. Thereis an opening opposite core N in plate A.

C is a metallic bridge plate with a projecting wing 10 from whichdepends a contact tip 11 which is preferably a plug of platinum. Thebridge plate is insulated by means of collars 12, 13 and is attached tothe top plate by means of posts 14 and nuts 15.

The spring armature plate D which may be stamped from one piece of sheetmetal and may be attached to the top plate by means of cars 20 and 21and suitable screws has a tail 25 which is bent up and back andterminates in arms 26 and 27.

My adjusting means comprises an adjusting nut F which has at the top aknurled rim 50 by which it may be turned by the fingers. At its middleportion, it has. an annular slot 51 into which the arms 26 and 27 enterand at its bottom it has a toothed rim 52.

Through the center of nut F is an axial threaded passage through whichpasses the lock screw 61. In the top of nut F is preferably a centralcylindrical cavity 53 which receives the head of lock screw 61 and inthe bottom is another central cylindrical cavity 54 to receive a checknut'62. This check nut 62 is preferably thin and can enter entirely intobottom cavity 54. Lock screw 61 passes through a threaded hole in topplate A and through a boss 72 formed therein.

The spring 80 carried by a spring post 81 engages the toothed rim 52 insuch a manner as to prevent the adjusting nut being I accidentallyturned.

In assembling my device at the factory, lock screw 61 is screwed throughthe adjusting nut and then the check nut 62 is screwed thereon. The lockscrew is then screwed through the top plate A and the collar 73 is fixedto the bottom end thereof preferably by spinning over the metal on theend of 61 so that after the top plate is in place, the adjusting meanscannot be removed without taking off the top plate and forcibly removingthe collar 73. It is desirable that such coils should be deliveredadjusted for a uniform quantity of current, but at the same time, thereshould be a moderate range of adjustment thereafter. With this device, Ican set the minimum tension adapted to the weakest working current andleave a limited range of adjustment for increasing that tension for anincreased current.

In adjusting at'the factory after the parts are assembled, the adjustingnut is screwed up to the highest point on the lock screw until stoppedby the head thereof. Then by means of a screw driver inserted in theslot in head 60 both are'turned down until the desired tension isobtained. This can be done while the circuit is closed and can berapidly and accurately standardized by connecting with and reading anelectrical indicator. To fix this minimum tension, the check nut 62 bymeans of a thin wrench is screwed down tight on the top of plate Awhereby the lock screw is prevented from being turned except by the useof excessive and unreasonable force. This is the position shown in Figs.3 and 4:. The adjusting nut can now be screwed downward on lock screw 61thus increasing the tension but cannot be screwed up beyond the headwhereby the minimum tension is fixed. The maximum tension in such caseis determined when the bottom of nut F strikes the top of plate A. Theparts must be so made that this maximum will not be excessive. It willbe seen, however, that the maximum bears no fixed relation to theminimum tension and the range of adjustment between the maximum andminimum varies.

The advantages of my construction are that the parts can be assembledcomplete and in proper condition for testing and then the adjusting nutcan be adjusted for the minimum tension desired, after which the partscan be so locked in place by means of the check nut and thin wrench thatthey cannot reasonably be tampered with thereafter by the user as he isnot likely to be provided with the special form of wrench or keynecessary to turn the thin check nut.

hat I claim as my invention and desire to cover by Letters Patent, is:

1. In a spark coil having a core and a top plate, the combination of aspring armature having a tail which terminates in arms, a lock screwwhich passes through the top plate and has a bottom collar fixed at itslower end and has a head at its upper end, and an adjusting nut throughwhich the lock screw passes having a top cylindrical cavity for thescrew head, a bottom cylindrical cavity and an annular groove on theoutside for the arms, with a thin check nut on the lock screw adapted toenter the bottom cavity in the adjusting nut as described.

2. In a spark coil having a core and a top plate, the combination of alock screw which passes through the top plate and has a bottom collarfixed at its lower end and has a head at its upper end, with anadjusting nut through which the lock screw passes having an annulargroove on the outside, a thin check nut on the lock screw between theadjusting nut and the top plate, and a spring armature having a tailwhich enters the annular groove on the adjusting nut as described.

In a spark coil having a core and a top plate, the combination of a lockscrew which passes through the top plate and has a bottom collar fixedat its lower end and has a head at its upper end, with an adjusting nutthrough which the lock screw passes having an annular groove on theoutside and a toothed rim at the bottom, a thin check nut on the lockscrew between the adjusting nut and the top plate, a spring whichengages the toothed rim of the adjusting nut, and a spring armaturehaving a tail which enters the annular groove on the adjusting nut asdescribed.

In testimony whereof I hereto atfix my signature in presence of twowitnesses.

BUTLER AMES.

\Vitnesses:

JoI-IN AMESFENNIG, FRANCES A. KANE.

G'opies of this patent may be obtained for five cents each, byaddressing the Commissioner of Patent!- Washington, D. G.

